150 MORPHOLOGY AND EVOLUTION particular fossil teeth are human or simian. In the Anthropoid Apes, particularly the Chimpanzee, the roots of the molar teeth diverge widely and reach the dental canal: and the small-pulp cavities are situated on the level of the necks of the teeth. In modern Man the roots of the teeth do not diverge much, nor do they reach the dental canal. The cavities are small and all lie above the alveolar border of the mandible, whereas they gradually sink lower down in the Apes in the order Ml, M>2, iI3. In some fossil Men the pulp-cavities are very large, but the roots of the teeth do not diverge as much as they do in the Apes ; and the pulp-cavities all lie at the same level.